Retirement Plans (Tables)

6 Months Ended

Jun. 30, 2023

Retirement Benefits [Abstract]

Net period benefit cost for the pension and postretirement plans

The components of net periodic pension cost and net periodic benefit cost for the RAP and Postretirement Plan for the three and six months ended June 30, 2023 and 2022 were as follows:

	Three Months Ended Jun 30,				Six Months Ended Jun 30,
($ in thousands)	2023		2022		2023		2022
RAP
Service cost	$	796	$	923	$	1,592	$	1,847
Interest cost	2,686		1,772		5,372		3,545
Expected return on plan assets	(8,202)		(6,736)		(16,404)		(13,472)
Amortization of prior service cost	(63)		(63)		(125)		(125)
Amortization of actuarial loss	—		74		37		147
Total net periodic pension cost	$	(4,783)	$	(4,029)	$	(9,528)	$	(8,059)
Postretirement Plan
Interest cost	$	20	$	13	$	39	$	27
Amortization of prior service cost	(19)		(19)		(38)		(38)
Amortization of actuarial loss (gain)	(7)		—		(15)		—
Total net periodic benefit cost	$	(7)	$	(6)	$	(13)	$	(11)